Cycling is not regarded as a dominant mode of transportation, especially in North America, primarily due to concerns for its safety and comfort. Understanding the perception of bicycle riders on safety and comfort is thus important for cycling friendly infrastructure and policies, yet there is lack of knowledge that can effectively assist project planning to promote the safe and comfort environment for cycling. An instrumented probe bicycle is designed and constructed to collect necessary motion critical data of a human-bicycle dynamic system, and a mobile app also is developed to collect risk factors. The research 1) investigates risk factors perceived by bicyclists; 2) analyzes how the motion dynamics data relates the rider’s level of cycling skills and bicycle safety; 3) determines the bike-ability in terms of safety and comfort on given bicycle environment by the level of cycling skills.